如何撰写高质量的流行病学研究论文 第一讲 遗传风险预测研究报告规范——GRjPS介绍

随着遗传流行病学的兴起,复杂疾病的遗传风险预测日益得到关注。近年来,遗传风险预测研究层出不穷,但其在报告的质量和完整性方面存在很大差别。对该类研究结果的正确评价有赖于规范、准确的报告：本文介绍加强遗传风险预测研究报告质量声明(Genetic Risk Prediction Studies,GRIPS)的清单内容,并对其中一些重要条目做详细说明。     

如何撰写高质量的流行病学研究论文第一讲观察性流行病学研究报告规范——STROBE介绍

观察性研究是流行病学研究的重要组成部分,主要用于探索和检验疾病与暴露之间的因果关联.观察性研究报告应当提供评价研究潜在偏倚和研究结论适用性的重要信息.不完整、不规范的报告会限制对研究有效性的评价.本文分析了影响观察性流行病学研究有效性的主要因素,在此基础上特别介绍了国际上为改善观察性研究论文的质量而建立的报告规范——加强观察性流行病学研究报告的质量（STROBE）的制定过程及清单内容.     

生活质量的流行病学应用

生活质量为流行病学研究提供了一种新的研究手段。对生活质量在健康流行病学、病因学研究与混杂分析中的应用，生活质量在临床流行病学、管理流行病学、健康状况影响因素与防范重点的探讨，生活质量在社区卫生服务等领域的研究和应用进行阐述，从三级预防的角度展示了生活质量在健康促进与疾病防治中的应用前景。     

脑瘫患儿生命质量流行病学研究进展

脑瘫患儿生命质量在近20年引起研究者广泛关注。对国内外近10年该领域流行病学研究进行综述，主要介绍了脑瘫患儿生命质量现况及影响因素的最新进展。开展大规模、基于人群的流行病学研究，寻找影响脑瘫患儿生命质量的主要因素，加强纵向研究是我国该领域未来研究的趋势。     

因果图模型及其在营养流行病学研究中的应用

不良饮食是慢性非传染性疾病最重要的可控危险因素之一,但通过随机对照试验定量阐明具体饮食因素与健康结局的因果关联面临很多困难。近年来,因果推断的迅速发展为充分利用和发掘观察性研究数据,产生高质量的营养流行病学研究证据提供了有力的理论和方法工具。其中,因果图模型通过整合大量先验知识将复杂的因果关系系统可视化,提供了识别混杂和确定因果效应估计策略的基础框架,基于不同的因果图,可选择调整混杂、工具变量或中介分析等不同的分析策略。本文对因果图模型的思想和各种分析策略的特点及其在营养流行病学研究中的应用进行介绍,旨在促进因果图模型在营养领域的应用,为后续研究提供参考和建议。     

流感疫苗效果评价的观察性流行病学研究设计中偏倚的处理方式

对于流感疫苗效果评价,随机对照试验是"金标准",但常常受到伦理学、研究资源等因素的限制而无法实施,观察性研究设计在此领域得到了广泛运用。但由于观察性研究可能存在着各种偏倚,严重影响了内在真实性,如何处理观察性研究中偏倚的影响,这是决定其能否成为有效证据的制约点。本文在阅读大量文献的基础上,对流感疫苗效果评价的观察性流行病学研究设计中偏倚的处理方式进行了综述,为今后同类的研究提供参考。     

近年来《中华流行病学杂志》上发表的横断面研究报告完整性评价

[导读]为了解近年来国内横断面研究报告的完整性,本文作者根据STROBE声明(第四版)制定了五部分39条的评价条目,对2006年1月至2008年4月在<中华流行病学杂志>上发表的概率抽样设计的横断面研究报告(合格论文共97篇)的完整性进行评价.39个条目的报告率分布:9个条目的报告率低于25%,4个条目的报告率界于25%～50%之间,7个条目的报告率界于50%～75%之间,19个条目的报告率高于75%.还有部分论文未在适当的位置上报告评价条目.与国际上较为公认的发表规范相比,国内学者在发表横断面研究论文时主要存在报告不完整和不规范两方面的问题.     

流行病学研究方法在生殖健康研究中的应用

流行病学研究方法在生殖健康研究中的应用可以追述到 19世纪初期。经典的例子是 :IgnazSemmelweis发现由医学生在医院接生的产妇死于产褥热者多于助产士接生者。通过观察 ,他将造成这种差异的原因归因于在两次接生之间的洗手问题。随着医学模式的转变和流行病学的发展 ,流行病学方法在生殖健康研究中的应用愈来愈广泛 ,渗透到生殖健康研究的各个领域。流行病学研究方法可用来确定生殖健康中的主要问题 ,阐明其原因和危险因素 ,进行预防干预实验并能够对所实施的项目进行评价[1 ] 。一、观察性研究观察性研究方法在生殖健康研究中应用最为广…     

流行病学研究新进展

流行病学是一门方法学与应用科学相融合的学科,预防和控制疾病、促进健康是其学科使命。本研究从传染病、慢性病、系统流行病学、实施性研究和健康医疗大数据5个方面介绍流行病学的新进展。传染病领域的新工程与不断涌现的新技术令人振奋,同时病原体变异的环境影响因素需得到更多重视。慢性病领域需更加重视老年人群共病问题;感染性诱发因素、人体菌群在慢性病发生发展过程中的作用逐渐被揭示。系统流行病学是现代流行病学的新兴分支与重要补充,对实现精准预防具有重要意义。实施性研究是连接医学基础科研与公共卫生实践的桥梁,将为健康中国行动计划的有效落实提供证据支持。健康医疗大数据的发展以数字化公共卫生为基础,为流行病学提供广阔的科研平台和丰富的数据资源,也将推动公共卫生服务管理模式的根本转变。     

营养流行病学队列研究中的膳食营养调查方法及应用

在一般人群中,尽可能减少受试者负担,且最大限度地正确评估日常膳食营养状态是构建营养流行病学队列研究的前提条件。本文介绍主要膳食营养评估方法的同时,着重说明食物频率问卷（food frequency questionnaire）开发的基本内容及其原则,并以天津营养流行病学队列研究（TCLSIH队列研究）调查为例,简单说明地区性食物频率问卷开发的问题点和解决策略。在此基础上,初步讨论全国版食物频率问卷开发的必要性和可能性。     

Strengthening the Reporting of Observational Studies in Epidemiology – nutritional epidemiology (STROBE‐nut): An extension of the STROBE statement

Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology – Nutritional Epidemiology (STROBE‐nut). Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, co‐ordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three‐round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health.     

Understanding Nutritional Epidemiology and Its Role in Policy

Nutritional epidemiology has recently been criticized on several fronts, including the inability to measure diet accurately, and for its reliance on observational studies to address etiologic questions. In addition, several recent meta-analyses with serious methodologic flaws have arrived at erroneous or misleading conclusions, reigniting controversy over formerly settled debates. All of this has raised questions regarding the ability of nutritional epidemiologic studies to inform policy. These criticisms, to a large degree, stem from a misunderstanding of the methodologic issues of the field and the inappropriate use of the drug trial paradigm in nutrition research. The exposure of interest in nutritional epidemiology is human diet, which is a complex system of interacting components that cumulatively affect health. Consequently, nutritional epidemiology constantly faces a unique set of challenges and continually develops specific methodologies to address these. Misunderstanding these issues can lead to the nonconstructive and sometimes naive criticisms we see today. This article aims to clarify common misunderstandings of nutritional epidemiology, address challenges to the field, and discuss the utility of nutritional science in guiding policy by focusing on 5 broad questions commonly asked of the field.     

Methodological approaches to study dietary patterns in relation to risk of coronary heart disease and stroke

Dietary pattern analysis, which reflects the complexity of dietary intake, has received considerable attention by nutritional epidemiology. For a long time, two general approaches have been used to define these summary variables in observational studies. The exploratory approach is based only on the data of the study, whereas the hypothesis-oriented approach constructs pattern variables based on scientific evidence available before the study. Recently, a new statistical method, reduced rank regression, was applied to nutritional epidemiology that is exploratory by nature, but can use scientific evidence by focusing on disease-related dietary components or biomarkers. Several studies, both observational and clinical, suggest that dietary patterns may predict the risk of CHD and stroke. In the present review, we describe the results of these studies and the available evidence regarding the relationships between dietary patterns and risk of CVD and we discuss limitations and strengths of the statistical methods used to extract dietary patterns.     

The role of epidemiology in developing nutritional recommendations: past, present, and future.

Observations of the relations between food choices and health have been made since ancient times, but epidemiology, which can be regarded as the science of systematically studying these relations, has played a key role in official nutritional guidance only in recent years. In the past 20 y the principal goal of nutritional guidance has changed from the prevention of nutritional deficiencies to the prevention of chronic diseases. This evolving purpose of nutritional guidance has demanded that nutritional epidemiology play an increasingly important role. Although no other type of nutritional science can equal epidemiology in the relevance of either the dietary exposures or the health outcomes, substantial problems limit the ability of nutritional epidemiology to convincingly prove causal associations. The classic criteria for causation are often not met by nutritional epidemiologic studies, in large part because many dietary factors are weak and do not show linear dose-response relations with disease risk within the range of exposures common in the population. The most important problem in nutritional epidemiology in the past has been the inaccuracy of dietary assessment. In the future, an additional problem will be the proliferation of hypotheses that can be tested in multiple ways among the many subgroups of the population that can be defined by factors such as age, sex, and genotype. Future progress in our understanding of the relations between diet and health will necessitate improved methods in nutritional epidemiology and a better integration of epidemiologic methods with those used in the clinical nutritional sciences.     

Mendelian randomization in nutritional epidemiology

Nutritional epidemiology aims to identify dietary and lifestyle causes for human diseases. Causality inference in nutritional epidemiology is largely based on evidence from studies of observational design, and may be distorted by unmeasured or residual confounding and reverse causation. Mendelian randomization is a recently developed methodology that combines genetic and classical epidemiological analysis to infer causality for environmental exposures, based on the principle of Mendel's law of independent assortment. Mendelian randomization uses genetic variants as proxies for environmental exposures of interest. Associations derived from Mendelian randomization analysis are less likely to be affected by confounding and reverse causation. During the past 5 years, a body of studies examined the causal effects of diet/lifestyle factors and biomarkers on a variety of diseases. The Mendelian randomization approach also holds considerable promise in the study of intrauterine influences on offspring health outcomes. However, the application of Mendelian randomization in nutritional epidemiology has some limitations.     

Tools for assessing quality and susceptibility to bias in observational studies in epidemiology: a systematic review and annotated bibliography

BACKGROUND: Assessing quality and susceptibility to bias is essential when interpreting primary research and conducting systematic reviews and meta-analyses. Tools for assessing quality in clinical trials are well-described but much less attention has been given to similar tools for observational epidemiological studies. METHODS: Tools were identified from a search of three electronic databases, bibliographies and an Internet search using Google. Two reviewers extracted data using a pre-piloted extraction form and strict inclusion criteria. Tool content was evaluated for domains potentially related to bias and was informed by the STROBE guidelines for reporting observational epidemiological studies. RESULTS: A total of 86 tools were reviewed, comprising 41 simple checklists, 12 checklists with additional summary judgements and 33 scales. The number of items ranged from 3 to 36 (mean 13.7). One-third of tools were designed for single use in a specific review and one-third for critical appraisal. Half of the tools provided development details, although most were proposed for future use in other contexts. Most tools included items for selection methods (92%), measurement of study variables (86%), design-specific sources of bias (86%), control of confounding (78%) and use of statistics (78%); only 4% addressed conflict of interest. The distribution and weighting of domains across tools was variable and inconsistent. CONCLUSION: A number of useful assessment tools have been identified by this report. Tools should be rigorously developed, evidence-based, valid, reliable and easy to use. There is a need to agree on critical elements for assessing susceptibility to bias in observational epidemiology and to develop appropriate evaluation tools.     

The role of epidemiology in determining when evidence is sufficient to support nutrition recommendations. Summary statement.

This statement summarizes the key points of discussion among a group of nutritional epidemiologists who met in Washington, DC, for 2 d in October of 1997 to reflect on the role of nutritional epidemiology in the development of dietary recommendations for the public. Although imprecision in the measurement of diet places limits on nutritional epidemiology, no other field of nutritional science can provide direct information on relations between nutrition and health in free-living human populations. Among the nutritional sciences, therefore, epidemiology was regarded as being critically important. Nutritional epidemiology can be improved in the future by the development of more precise measures of long-term dietary exposures, both by improved methods of self-reporting of diet and by the development of more useful biomarkers of long-term nutritional status. There is a need as well to reconsider the applicability of causal criteria as applied to nutritional epidemiology, because many of the important associations between dietary behaviors and chronic diseases cannot necessarily be expected to be either strong or to manifest linear dose-response relations. In the future, scientific evidence from the rapidly growing field of nutritional epidemiology will likely play an increasingly important role in developing nutrition policy and advice for the public.     

Assessing the feasibility of Nipah vaccine efficacy trials based on previous outbreaks in Bangladesh

BackgroundNipah virus (NiV) is an emerging, bat-borne pathogen that can be transmitted from person-to-person. Vaccines are currently being developed for NiV, and studies have been funded to evaluate their safety and immunogenicity. An important unanswered question is whether it will be possible to evaluate the efficacy of vaccine candidates in phase III clinical trials in a context where spillovers from the zoonotic reservoir are infrequent and associated with small outbreaks. The objective of this study was to investigate the feasibility of conducting a phase III vaccine trial in Bangladesh, the only country regularly reporting NiV cases.MethodsWe used simulations based on previously observed NiV cases from Bangladesh, an assumed vaccine efficacy of 90% and other NiV vaccine target characteristics, to compare three vaccination study designs: (i) cluster randomized ring vaccination, (ii) cluster randomized mass vaccination, and (iii) an observational case-control study design.ResultsThe simulations showed that, assuming a ramp-up period of 10 days and a mean hospitalization delay of 4 days,a cluster-randomized ring vaccination trial would require 516 years and over 163,000 vaccine doses to run a ring vaccination trial under current epidemic conditions. A cluster-randomized mass vaccination trial in the two most affected districts would take 43 years and 1.83 million vaccine doses. An observational case-control design in these two districts would require seven years and 2.5 million vaccine doses.DiscussionWithout a change in the epidemiology of NiV, ring vaccination or mass vaccination trials are unlikely to be completed within a reasonable time window. In this light, the remaining options are: (i) not conducting a phase III trial until the epidemiology of NiV changes, (ii) identifying alternative ways to licensure such as observational studies or controlled studies in animals such as in the US Food and Drug Administration’s (FDA) Animal Rule.     

History and Impact of Nutritional Epidemiology

The real and important role of epidemiology was discussed, noting heretofore unknown associations that led to improved understanding of the cause and prevention of individual nutritional deficiencies. However, epidemiology has been less successful in linking individual nutrients to the cause of chronic diseases, such as cancer and cardiovascular disease. Dietary changes, such as decreasing caloric intake to prevent cancer and the Mediterranean diet to prevent diabetes, were confirmed as successful approaches to modifying the incidence of chronic diseases. The role of the epidemiologist was confirmed as a collaborator, not an isolated expert of last resort. The challenge for the future is to decide which epidemiologic methods and study designs are most useful in studying chronic disease, then to determine which associations and the hypotheses derived from them are especially strong and worthy of pursuit, and finally to design randomized studies that are feasible, affordable, and likely to result in confirmation or refutation of these hypotheses.As large databases from epidemiology studies become more available and papers using their large amount of information proliferate, there is a tendency for conclusions of those papers to achieve the status of answers rather than as the lead point for prospective studies to confirm or refute the associations suggested by epidemiologic methods. In this setting, it seemed appropriate to review the contributions that epidemiology made to the knowledge base in nutritional sciences to better understand the role of the plethora of papers in nutritional epidemiology that now fill our journals.Dr. Alpers introduced the session by explaining the above rationale for the session. He pointed out that randomized controlled trials (RCTs) are the gold standard in clinical research and that these would be preferred for nutritional studies. However, there are difficulties in using foods or nutrients as interventions in RCTs. These difficulties include having the wrong proportion of food intake assigned to the diet, testing the wrong dose of nutrient, getting the duration of intervention wrong, intervening too late to alter the natural history of the disease under study, and not being able to correct for confounding factors, among which are lifestyle biases, genes, environmental effects on genes, or non-nutrient constituents of foods. For these and other reasons, data on the effect of diets or nutrients in chronic disease are dependent on observational studies to produce associations and derive hypotheses for additional testing. Such studies can be very useful, but when individual nutrient intervention were used to confirm hypotheses, the results did not in general confirm the implications from the associations identified in observational studies. Confirmation was found using whole diets or dietary patterns (e.g., Mediterranean) or whole food classes (e.g., whole grains), but the individual nutrients responsible for the confirmed observations found with food are not known. This symposium includes talks that use examples from the history of the field of nutritional epidemiology to demonstrate when epidemiology led to considerable advances but also to note the areas in which this methodology was not so successful and to exercise caution in the interpretation of the resulting associations.Dr. Carpenter was unable to attend, but his talk was interpreted by Dr. Bier, who spoke on the “Historical Role of Epidemiology in Identifying Essential Nutrients.” He expanded on Dr. Carpenter’s selected example of the successful use of epidemiology in the discovery of the cause and prevention of beriberi. In his historical exposition, Dr. Carpenter chose to highlight the less well known story of Hamilton Wright, who studied beriberi in Malaya, then a British colony. Wright recognized that Malaya was an optimal location to study beriberi because the country was inhabited by 3 Asian populations whose different environmental conditions and habits might provide clues to the origin of the disease. He noted that, although Chinese brought in to work in the tin mines commonly developed beriberi, native Malays and Tamils imported from Sri Lanka did not. However, when imprisoned in a multiracial prison, all were similarly susceptible to the disease. Among other differences identified in the free-living populations, he realized that the Chinese ate “Siam” (white) rice and the Tamils ate “Bengal” (parboiled) rice. However, based on his medical training, including the recently appreciated germ theory of disease, and the limits of nutritional knowledge at the time, Wright persisted in his belief that the disease was caused by an unknown organism that entered the body by mouth with subsequent gastrointestinal production of a toxin responsible for the signs and symptoms of beriberi. Shortly thereafter, Dr. W. L. Braddon realized that Wright’s interpretation was mistaken and that the disease was a dietary disease. He recognized the importance of the fact that the Chinese ate Siam rice and that parboiling (Bengal) rice afforded protection against beriberi. He further appreciated that, although Malays ate Siam rice, it was often consumed freshly after winnowing. Thus, although he realized that beriberi was dietary in origin, he interpreted his findings as an indication of a toxin present in the rice. Understanding how to prevent the disease required a prospective experiment, then performed by Walter Fletcher, the senior physician at the Insane Asylum in Kuala Lumpur, where a beriberi outbreak had just occurred. Dr. Fletcher did not believe Dr. Braddon’s hypothesis, so he decided to test it by feeding inmates in 1 building Siam-style rice and in another building parboiled rice, cooked in the Tamil way. He found that 18 of 120 individuals fed Siam-style rice died compared with 0 of 120 fed Tamil rice. Fletcher rightly attributed the advantage as showing that white rice was deficient in a “dietetic value.” The irony of these findings was that, because of the poor medical communications of the time, the British experiments took place after earlier studies nearby in Asia already demonstrated the essential role of nutrient-deficient rice in the pathogenesis of the disease. In Japan, Kenehiro Takaki appreciated that kakké (beriberi) was the consequence of a rice diet, although he attributed the problem to protein deficiency, and Christiaan Eijkman in Indonesia, after an exhaustive series of experiments to eliminate alternative explanations possible from the observational data, came to the realization that the rice pericarp “silver skin” contained something essential for health. Although he did not identify the factor as thiamine, he shared in the Nobel Prize for this work that progressed from the observations on ingested rice to an identification of the source of the material that treated the disease. Dr. Bier concluded by noting that epidemiologists, clinical scientists, and chemists in this discovery process acted as collaborators, not rivals, but that the unraveling of the dilemma took time and studies in the field had to be designed to answer the hypothesis first established by epidemiologists.Dr. Donald McCormick followed by speaking on the role of epidemiology in decision making for food fortification, using examples of many micronutrients. He initiated the discussion by noting that food fortification has clear benefits for certain portions of the population and, as examples, used folate addition to foods to aid pregnant women in preventing deficiency and lowering the incidence of neural tube defects in the fetus and vitamin D added to milk to prevent rickets. However, he noted the increasing tendency for the false expectation that food fortification at amounts higher than needed to prevent deficiency might decrease nondeficiency diseases. These expectations are often initiated by epidemiologic studies. The data with folate supplements and their role in preventing colorectal cancer are mixed, showing an inhibitory effect in individuals who are folate deficient but a promoting effect on the progression of established neoplasms. Similarly, the benefit suggested for vitamin D by epidemiologic studies in conditions as diverse as cancer and heart disease has yet to be confirmed by prospective RCTs. When there is no evidence of deficiency, current RDA amounts of intake should suffice for most people. However, the difficulty in defining and agreeing on a biochemical definition of the deficiency state continues to plague the field of micronutrients (e.g., vitamins B-12 and D) and led to additional confusion about how to translate the findings from epidemiologic studies into prospective trials that will provide definitive answers.Dr. Anthony Miller then addressed the role of epidemiology in identification of foods and nutrients that influence the risk of cancer. He first discussed study designs beginning with correlative/ecologic studies. They further include case-control studies in which biases need to be recognized and cohort studies in which recognition of misclassification is important. Finally, intervention studies designed to confirm observed associations from the first 2 study types often use surrogate endpoints to detect premalignant changes, but when cancer is the endpoint in a study of finite length, the length of follow-up and timing in regard to natural history becomes very important. A number of non-interventional studies were reviewed initially, demonstrating that increased total calories were associated with increased risk of cancer but showing rather little specificity for specific macronutrients or food components. Although some studies demonstrated a reduced risk with increased intake of fiber or vegetable and fruit, other studies did not confirm these associations. The best associations continue to reflect cancer risk that is increased by higher caloric intake or decreased risk when following a total diet, such as the Mediterranean diet. Interventional studies, exemplified by β-carotene and vitamin A supplementation, mostly failed to reduce risk. The current period of increased interest in genetics was discussed, noting that multiple single-nucleotide polymorphisms in genes were tested for their association with cancer risk and that small effects were seen that need replication. These may indicate individual susceptibility, but in addition, these studies tend to ignore the effects of dietary factors. Thus, the role of cancer prevention by dietary change may have been downgraded in the recent literature. Dr. Miller concluded that improved calibration of nutrient intake improved our recognition of associations but that misclassification of dietary intake (e.g., red meat, fiber) impaired our ability to detect causal associations, if they truly exist. He also concluded that the effects of dietary patterns need to be pursued and that we not be misled or sidetracked by genetic associations, each of which may account for only a small portion of the cancer risk in a population-based study. This is important, because cancer risk seems to be increasing as a function of increased weight/obesity, but it is not certain whether this is all due to increased caloric intake or whether individual dietary components play a role.Dr. Paul Jacques in his discussion of “The Relevance of Nutritional Epidemiology in the 21st Century” provided additional historical examples of successful confirmation of observational hypotheses with a focus on foods and dietary patterns and noted 1 future direction for the discipline. He reviewed the data on an association between ingestion of whole wheat and favorable health outcomes in diabetes and cardiovascular disease and the resulting interventional studies that confirmed the benefit of ingesting whole-grain foods. He followed this with the data on the Mediterranean-style dietary pattern, again confirmed by interventions on the incidence of diabetes and cardiovascular disease. These examples demonstrated the consistency between the evidence provided by the observational studies and intervention trials. However, as reviewed in cancer outcomes by Dr. Miller, clear epidemiologic data on the role of individual nutrients is more difficult to obtain. Thus, Dr. Jacques noted that 1 direction for the future of nutritional epidemiology was to use metabolomics to identify metabolites (not nutrients) associated with the individual foods and dietary patterns and by quantifying their potential to uncover diet–disease relations in populations. He concluded that, although traditional approaches continue to provide valuable knowledge about the cause of chronic diseases, new technologies will be essential to maximize the impact of epidemiology in the future.     

Varicella surveillance practices--United States, 2004

Varicella became a reportable disease in the United States in 1972, with states reporting weekly aggregate data to the National Notifiable Disease Surveillance System (NNDSS). In 1981, varicella reporting was removed from the national notifiable diseases list because reporting of this common disease was becoming a burden in the absence of a vaccine. This action was followed by additional changes in varicella surveillance practices. In 1995, varicella vaccine was licensed and added to the routine childhood vaccination schedule. In 2002, the Council of State and Territorial Epidemiologists (CSTE) recommended that varicella casebased surveillance be implemented in all states by 2005; in 2003, varicella again was added to the national notifiable diseases list to allow for monitoring of the effect of varicella vaccine on varicella incidence. In 2004, to assess the progress in varicella surveillance in the United States, CDC surveyed immunization program managers in selected public health jurisdictions. This report describes the results of that survey, which indicated that substantial progress has been made toward the implementation of case-based surveillance as recommended by CSTE in 2002. As of 2004, however, 28 jurisdictions still had not implemented case-based surveillance. To monitor the effect of the vaccination program on the changing epidemiology of varicella disease, every state should now be conducting case-based surveillance for varicella. This is particularly important in light of the 2006 recommendation by the Advisory Committee on Immunization Practices for a routine second dose of varicella vaccine for children aged 4-6 years because enhanced surveillance is needed to further monitor varicella epidemiology.